Lubricating and insulating compound



Patented June 2 2, 1937 t 'UNITED STATES PATENT oFFic Peter J. Wiezevich, Elizabeth, N. 1., assignor to Standard Oil Development Company, a "cor poration of Delaware NoDrawing., ApplicationJuly 14, 1934, Serial a 12 Claims. (01. 87-9) p The presentinvention relates to improvements as 0.05% is often suflicient, but usually,0.1%

in lubricating and insulating compounds and will be used. In rare instances more than 0.5%

more speciflcally to inorganic, acid ester commay be employed but in practically all cases the j pounds, "llhepresent invention is a continuation amount used is less than 1%.

in part of a prior application, Serial No. 690,770, -To illustrate the effect ofthe inhibitors on the filed September; 23, 1933, and will be fully underoxidation of these esters the following tests may stood from the following description. be considered: r M

In the previous application referred to above Example 1 cer ain inorganic acid esters, especially the aromatic phosphoric esters, were disclosed as safety -u case the ester compound was 10 qlubpi cants, especially turbine oils, because in I cresyl phosphatie of technical or coljamerc addition to the primary requisites such as visgrade Its Speclficatmns rare as follows cosity,o11iness and the like, those materials are Viscosity 100 F. 132 sec. Saybolt characterzedby high fiashand ignition tern-v Viscosity 210 F 39.4 sec.Sa'-bolt c, peratures. [The same is also true of boric esters. Demulsibility -Q 1620 15 Bothof these classes of compounds are not only Pour point F.

applicable as lubricants but also make excellent Flash 450 F.

insulating oils for transformers, switches, sub- Auto ignition temperature l Above 1000 F.

i mm sion type circuit breakers and the like. The above product and the same to which had The esters which are of the greatest value are l M 0 y l been added 0.1% ofalpha thionaphthol were sub- 20 me aryl that Is to say phenolic esters of phos mitted to oxidation absorption tests. In these phoric and boric acids, particularly the alkylated aryl esters Such as triwrthmcresyl phosphate, tests air is bubbled in a closed circuit through the but the aliphatic esters are suitable as well. on (10 sample) whne maintained at 200 l One diflicult with these ,materials a ears to at 15 minpte intervals The amopnt of oxygen be their tendezmyvat least in the tecggical or absorbed is determined by the difference from 25 commercially available grades, to deteriorate at the amount remaining elevated temperatures, with formation of acidity, C bs b d l but it has now been found that this can be res i mi 2 duced to an unobjectionable degree by the addisamp e) W s 30 tion of oxidation inhibitors, 1 2 3 4 6 6 7 8 I ib 'n a t w gi f gl 50111218 in Tri-ortlio-eresyl phosphate 73 272 Too rapid to meas-' es er compoun s are sui a e or e presen puru posel and among those may be mentioned pap Same+.1% alpha thio naphthoL.-. 11 26 36 17 l8 14 12 9 5 ticularly the phenol types, especially the polyhydroxy, monocyclic compounds, such as resorci- Emmple 2 1101, Pymgauol and the like, and the a In another test the blank sample (300 c. c.) poly-hydroxy bicyclic aromatic materials such and the same containing alpha naphtha as the alpha e naphthols' Aromatic amim were blown with air while at 300 F. at a rate of 40 compounds are also satisfactory, such as the 10 cubic feet per noun The acidity was meas 40 naphthyl amines Aromatic sulphur compounds ured at intervals and the data recorded in the are also efiective, such as thiophenols and naphtable below,

a thols, sulphides, disulphides and the various polysulphides. Ordinary others, but especially thioethers, containing at least one aromatic radical can be used and such radical may be sample either purely hydrocarbon or substituted, for exahrsflhrs- 241m 751m ample, containing a hydiioxyl or armiro firailipt; a l The above will serve to ilustrate e ac a Blank .20 .31 1.2 1.39 l all of the known types of inhibitors whigh ar Bamp1e+.11% naphthol .13 .13 .21 .54 50 r suit le for l ig fif g 'fng fig g e a These latter samples were also submitted to Acidity mg. K OH/gr.

The-amount of inhibitors will vary somewhat, Sligh t the blank w n me. Wh l th depending on their inherent strength, but in all inhibitor reduced this to 1.6 mg. in the sample cases the amount is minute, for example as little to which it was added, 55

I To these inhibited esters may be added thickeners, soaps, sludge dispersers, bases, oiliness agents, extreme pressure lubricating agents and other known blending agents which maybe desirable to adapt; the material to some specific purpose. 1 r

The present invention is not vto be limited by any theory of the mechanism of the inhibitor action or to any particular inhibitor or ester but only to the following claims in which it is desiredto claim all novelty inherentin the invention.

. I claim: v a

1. Composition of matter comprising an organic ester of an inorganic acid and not over 1% of an oxidation inhibitor selected from the class consisting of phenols, amino compounds, aromatic sulfur compounds, ethers and thio ethers containing at least on aromatic radical.

2. Composition according to claim 1 in which theester contains aromatic nuclei comprising at least'50% of they weight ofthe'ester,

' '3. Composition of' matter comprising the organic ester of an acid selected-from the group of phosphoric and boric and not over 1% of an oxidation inhibitor selected from the class consisting of phenols, amino compounds, aromatic ,sulfur compounds, ethers and thio ethers containing at leastone aromatic radical.

' 4. Composition according to, claim 3 in which the ester is a phenolic ester.

5. Composition according to claim 3 in which the ester is a phenolic ester of phosphoric acid.

6. Composition according to claim 3 in which the ester is tricresyl phosphate.

7. Composition of matter comprising tri-ortho cresylphosphate and not over 1% of an oxidation inhibitor selected from the class consisting of phenols, amino compounds, aromatic sulfur compounds, ethers and thio ethers containing at least one aromatic radical.

8. Composition according to claim 7 in which the inhibitor is an aromatic compound containing a radical selected-from the group of hydroxy the inhibitor 'is thionaphthol.

PETER J. WIEZEVICH. 

